DNA transcription and translation question

Question

What organelle contains all of the mechanisms required to undergo their own protein synthesis and why?

(The organelle must be one that does not already undergo protein synthesis, but rather has the right mechanisms to do so)

Answer 1

For animal eukaryotic cells, the mitochondria would be the correct organelle. Mitochondria have their own ribosomes and their own DNA that is separate from the cell that it resides in. Thus, it has the correct machinery to perform protein synthesis on its own. A strong theory in science is that the mitochondria was once its own prokaryotic cell that underwent endocytosis into a another cell and got incorporated into the cytoplasm (this is called the theory of endosymbiosis). This explains the mitochondria having the ability to carry out protein synthesis on its own. The same theory goes for the chloroplast.

Answer 2

Mitochondria and chloroplasts have their own DNA (separate from the DNA located in the nucleus of a cell). On top of having their own DNA, they have their own gene expression machines, namely ribosomes which are the site of protein translation. So these two organelles are capable of making their own proteins.